The split, led by Giuseppe Saragat and the sons of Giacomo Matteotti, took the name of scissione di Palazzo Barberini from the name of a palace in Rome where it took place. In 1952, the party ultimately became the Italian Democratic Socialist Party, after joining forces with the smaller Unitary Socialist Party (PSU) in 1951.

From 1949 to 1965 members of the PSDI held the presidency of the Istituto Nazionale di Previdenza Sociale (INPS).[6]

The party was re-established in 2004 with the same name, "Italian Democratic Socialist Party", as the continuation of the party of Saragat, so that the new PSDI numbers its congresses in perfect continuity with the late PSDI.